XAIN – access control protocol for the mobility sector

XAIN is developing a blockchain-based access control protocol for machines, focusing on the mobility sector. It was co-founded by Leif-Nissen Lundbæk (CEO), Felix Hahmann (COO), and Prof. Michael R. A. Huth (CTO). XAIN is headquartered in Germany, Berlin and has scientific roots. Prior to its foundation in 2017, it started as a research project at the University of Oxford.

Due to their focus on the mobility sector, their clients are, among others, some of the biggest car manufacturers worldwide such as Volkswagen, Daimler, or Porsche [1]. Besides that, XAIN won Porsche’s „Porsche Innovation Contest“ and has since partnered with the German car manufacturer [2]. Additionally, they are in a partnership with Daimler and NVIDIA [3] and is also part of MOBI, the Mobility Open Blockchain Initiative [4].
Recently, XAIN received a €6 Million investment, led by Earlybird.

The technology

The XAIN Blockchain is private blockchain based on Ethereum. Among other things, this means that XAIN’s nodes are neither rewarded nor incentivized for mining, and XAIN decides who can be a node. Furthermore, miners in the blockchain are controlled by a known entity (e.g. a company that has implemented XAIN) and the hardware behind the nodes is homogenous; those nodes are per default stored on microcontrollers and might be included into machines such as cars.

XAIN has implemented Proof of Kernel Work (PoKW). PoKW is an adaption of Proof of Work (PoW) with a kernel reduction. Through this kernel reduction, XAIN wants to limit the number of mining nodes in each mining action. The used nodes are known to XAIN, and for each new block, a random subset of these nodes is selected for mining. This whitelisted mining process should, among other things, make mining less computational costly so that I can run on smaller devices. Such energy-efficient mining should make the blockchain well-suited for use cases in the IoT-sector.

Use cases

At its core, XAIN is an access control protocol for managing human-machine interactions. Access control refers to authentication, validation, execution, and logging of human interactions with machines such as cars. XAIN then uses their blockchain to store theses access permissions and transactions (i.e. when somebody accessed a machine).
Access control enables several connected cars use cases. XAIN has demonstrated two of them, data logging and access control itself, in a demo with Porsche.

Access control

By connecting cars to the XAIN blockchain, car access can be managed remotely. Through that, a car owner can grant temporary access to the car (e.g. package trunk delivery) or lock/unlock cars remotely.

Data logging

By integrating their hardware nodes into cars, their blockchain logs driving data and stores it on the InterPlanetary File System (IPFS). This data can be used to analyze driving behavior.
Although not implemented it, data logging enables use cases beyond the analysis of just driving behavior.

Data gathering for decentralized machine learning

As explained in data marketplaces for decentralized machine learning, especially autonomous cars need a lot of training data. Because one manufacturer cannot accumulate all that training data on its own, data marketplaces where training data can be bought, provide one great solution here. Thus, thecaptured data can then be exchanged on such marketplaces.